 So value in inventory, you must value your inventory at the beginning and end of each tax year to determine your cost of goods sold schedule C line 42. So we're going to have to do that cost of sold goods sold calculation beginning inventory plus purchases mining minus ending inventory equals cost of goods sold in essence. Meaning that means that our beginning inventory should match what was the ending inventory in the prior tax return. If we had a prior tax return for the business, in other words, if it's not a new business and then we're going to have to have the purchases, which again might be the area that you kind of back into using algebra. Minus the ending inventory, which oftentimes you would determine making a physical count and just and and using your accounting records to determine what ending inventory is equals the cost of goods sold, which you might have in your accounting records. If you're using a perpetual inventory system, for example, already to calculate the cost of goods sold, which means you can possibly back into the purchases if you need to in that condition. So to determine the value of inventory, you need a method for identifying the items in your inventory and a method for valuing these items. So usually you've got the cost, but then obviously the cost of the inventory could have changed over time, usually going down over time. So if you're holding onto old inventory, it may not be worth what it was when you bought the inventory. You might have to use a flow assumption first in first out life of weighted average inventory valuation rules cannot be the same for all kinds of businesses. The method you use to value your inventory must conform to generally accepted accounting principles for small business and must clearly reflect income. So your inventory practices must be consistent from year to year. Obviously that consistency once again, something that we have to be consistent with otherwise there could be manipulation in. So if you changed from, for example, flow assumptions first in first out to last in first out to weighted average, you can severely change the value of your inventory. And that would be manipulative thing to do for most part. So more information for more information about inventory, you could see publication 538.